Inorganic-organic polymers with barrier properties for water vapor, oxygen and flavors

With a new kind of barrier coating material, inorganic-organic polymers, it is possible to obtain high-barrier properties with respect to the permeation rates of oxygen, water vapor and volatile organic compounds. The hybrid polymers are accessible via the sol-gel technique. The inorganic network is formed as a result of controlled hydrolysis and condensation of alkoxysilanes, organoalkoxysilanes, acryloxysilanes or metal alcoholates. The organic network results from subsequent thermal or UV-induced polymerization of organo-functional groups. Due to the control of the inorganic and organic network densities and the insertion of specific functional groups to control the polarity of the resulting material, it was possible to develop high-barrier coatings with excellent adhesion properties on a wide variety of polymer films. These high-barrier coatings are also suitable as adhesives which can be used in laminates. The properties of the processable multilayer structures are preserved to a much higher extent than with other comparable, commercially available materials even under high mechanical and thermal stress and storage in humidity.